The use of laser-imaged printing plates has become state of the art. Such plates are coated with infrared-sensitive organic photoconductors sensitive to light in the wavelength range of 700-900 nm. Typical inorganic photoconductors and a wide variety of organic photoconductors do not ordinarily exhibit the required sensitivity in the infrared region.
Large amounts of the infrared-sensitive organic photoconductors are ordinarily required to produce plates with the requisite level of sensitivity. However, the cost of using such large amounts of infrared-sensitive organic photoconductors makes the cost of such plates prohibitively high.
It has now been found that an effective photoconductive composition having the required sensitivity in the infrared region can be formulated with relatively modest amounts of the infrared-sensitive organic photoconductor.